A bit more, it seems you are making a poster and this type of question has come up for as long as Gimp has been around.
New user, working in real world units, while Gimp is working in pixels. For a 24 x 36 inch image, you, the user have to define a printing resolution. That might be 300 ppi as Ofnuts mentioned, more likely to be less, say 200 ppi or 150 ppi but not as low as a default 72 ppi or 96 ppi.
If you do not want to go into the gory details, then scale the pattern to suit.
Right click on the pattern. Open as image. Scale the pattern image up or down. Image > Scale Image Then for immediate use, Edit > Copy
That becomes the Pattern clipboard (the temporary first pattern). Use that to fill.
Those gory details.
https://youtu.be/31QxUU8OTTo How image ppi affects pattern size.
https://youtu.be/lMaIitnVg48 Scaling a pattern.
The stock Gimp patterns, such as the leopard pattern go way back, nothing has changed, what you get is what you see. If you need other patterns then you need to install yourself. A pattern does not need to be Gimp .pat format, .png and .jpeg also work.
New user, working in real world units, while Gimp is working in pixels. For a 24 x 36 inch image, you, the user have to define a printing resolution. That might be 300 ppi as Ofnuts mentioned, more likely to be less, say 200 ppi or 150 ppi but not as low as a default 72 ppi or 96 ppi.
If you do not want to go into the gory details, then scale the pattern to suit.
Right click on the pattern. Open as image. Scale the pattern image up or down. Image > Scale Image Then for immediate use, Edit > Copy
That becomes the Pattern clipboard (the temporary first pattern). Use that to fill.
Those gory details.
https://youtu.be/31QxUU8OTTo How image ppi affects pattern size.
https://youtu.be/lMaIitnVg48 Scaling a pattern.
Quote:...Also what is the last full version where the patterns were already installed? ..
The stock Gimp patterns, such as the leopard pattern go way back, nothing has changed, what you get is what you see. If you need other patterns then you need to install yourself. A pattern does not need to be Gimp .pat format, .png and .jpeg also work.